The present invention relates to electric bicycles and in particular a mid-drive arrangement for electric bicycles.
In the electric bike market, the “hub” or in-wheel motor has been the dominated configuration. Unfortunately, in in-wheel motor bicycles, there is no way to give a mechanical advantage to the motor using a conventional bicycle transmission. Additionally, when using an in-wheel motor configuration, the rider may input power through the pedals and into a conventional bicycle transmission however, because there is no direct connection between the wheel motor and transmission, it is possible for the rider to choose a gear ratio on the transmission which fails to transfer the rider's power input into the pedals as a useful addition to the bicycle's propulsion. As a result, there is an increasing movement away from an in-wheel motor and there is a need for better alternative motor configurations.
Mid-motor drive systems have been developed to replace wheel motor based electric drives, but known mid-motor designs use a complicated set of gears to combine the power of the motor with the rider power input through the pedals and then transfers all that power to a conventional bicycle transmission. This design often makes it impossible to operate the motor without rotating the pedals via an independent throttle such throttle driven operation being desirable by many consumers. Thus, a need remains for an improved mid-motor drive system.